Given the scope of the Ebola outbreak unfolding in Western Africa, it seems possible that a case will eventually emerge in the U.S.
We could even see an isolated cluster of infections in an American city.
Yet given the deadly nature of the Ebola virus, and the popular worry it's likely to engender, one can expect the CDC and health authorities to pull out all the stops. The response could include invocation of the CDC's evolving quarantine authorities.
These federal powers comprise a set of rules that gives CDC sweeping authority to hold and isolate Americans in a public health emergency. These authorities haven't been fully updated in decades. They've only been amended in piecemeal fashion to deal with modern threats like SARS and MERS. In advance of what may be a very public test of these powers, the collected scheme deserves closer scrutiny.
The regulations also defined "ill person" to include anyone with the signs or symptoms commonly associated with the diseases in question. This gave CDC more flexibility in deciding whom to quarantine by capturing a broader and earlier range of symptoms as the basis for holding an individual. It allowed for greater exercise of discretion public health officials and those staffing quarantine stations.